Ischnothyreus habeggeri Richard

Richard, Miguel, Graber, Werner & Kropf, Christian, 2016, The goblin spider genus Ischnothyreus (Araneae, Oonopidae) in Java and Sumatra, Zootaxa 4151 (1), pp. 1-99 : 50-55

Ischnothyreus habeggeri Richard , sp. nov.

( Figs. 38–42 )

Type material. Holotype: male (PBI_OON00052379), SUMATRA: N . Sumatra, Gn. Leuser Ketambe, l. litter trail 10, June 7 +27, 1986, leg. Suharto, Coll. Deeleman, NNM Leiden.

Paratypes: 2 males (PBI_OON00031849), collected with holotype.

Additional material examined. 1 male (PBI_OON00032334), SUMATRA: N . Sumatra, Gn. Leuser Ketambe, March 2–4, 1986, leg. Suharto, Coll. Deeleman, NNM Leiden.

Etymology. The species epithet is dedicated to Benjamin Habegger from Kirchberg-Alchenflüh, BE, a good friend and supporter of the author.

Diagnosis. Males of I. habeggeri sp. nov. resemble males of I. culleni Edwards & Harvey, 2014 in palps and chelicerae but can be identified by the shape of the tip of the bulb which is blunt and knob-like, making it look like a handlebar ( Figs. 40 A–H). The buckling on the height of the retrolateral lobe appears wrinkled (rl, w, Fig. 40 F, H). The shape of the cheliceral fang process (p, Figs. 41 B–D) is characteristic too and not as flat as in the other two species.

Description. Male: (PBI_OON00052379). Total length 1.85; carapace length: 0.90; carapace width: 0.72; abdomen length; 0.91.

CEPHALOTHORAX: Carapace pale orange, broadly oval in dorsal view, pars cephalica strongly elevated in lateral view, anteriorly narrowed to 0.49 times its maximum width or less, surface of elevated portion of pars cephalica smooth, sides finely reticulate; lateral margin straight, smooth. Clypeus margin unmodified, straight in front view, sloping forward in lateral view, high, ALE separated from edge of carapace by their radius or more. Eyes six, well developed, ALE largest, ALE circular, PME squared, PLE oval; posterior eye row straight from above, procurved from front; ALE touching, ALE-PLE touching, PME touching throughout most of their length, PLE-PME touching. Sternum as long as wide, pale orange, uniform, surface smooth, microsculpture absent, lateral margin without infra-coxal grooves, distance between coxae approximately equal, extensions of pre-coxal triangles absent, lateral margins unmodified; setae dark, needle-like, evenly scattered, originating from surface. Mouthparts: Chelicerae, endites and labium pale orange. Chelicerae straight, anterior face unmodified; directed medially, shape normal, tip unmodified; setae dark, needle-like, evenly scattered. Fang base with process (ca, Figs. 41 B–D). Labium rectangular, not fused to sternum, anterior margin not indented at middle, same as sternum in sclerotization; with setae. Endites distally not excavated, anteromedian tip with one strong, tooth like projection, much more heavily sclerotized than sternum.

ABDOMEN: cylindrical, rounded posteriorly; dorsum soft portions white, without color pattern. Posterior spiracles not connected by groove. Scutum extending far dorsal of pedicel. Dorsal scutum strongly sclerotized, yellow-brown, without color pattern, covering more than 3/4 of abdomen, more than 1/2 to most of abdomen width, not fused to epigastric scutum, middle surface smooth, sides smooth. Epigastric scutum weakly sclerotized, surrounding pedicel, not protruding, small lateral sclerites absent. Postepigastric scutum weakly sclerotized, yellow, short, almost rectangular, covering about 1/3 of the abdominal length, fused to epigastric scutum, anterior margin unmodified. Dorsum setae present, dark, needle-like. Spinneret scutum with fringe of needle-like setae. Interscutal membrane with setae.

LEGS: pale orange, without color pattern; patella plus tibia I longer than carapace, tibia I unmodified. Leg spination: femora: I p0-2-0; II p0-0-1; tibiae: I, II p2-2-0; r2-2-0; metatarsi: I, II p1-1-0; r1-1-0.

GENITALIA: Bulb with one large flat ventral protuberance, retrolateral lobe characteristic (rl, Figs. 40 F, H). Tip of bulb slightly elongated, blunt, knob-like, bent dorsally, with strong retrolateral wrinkles at buckling between bulb and embolus (w, Fig. 40 F).

Female: Unknown.

Distribution. Known only from Gunung Leuser Ketambe in northern Sumatra.

Figures

FIGURE 38. Ischnothyreus habeggeri sp. nov. Male: A, habitus, dorsal view; B, habitus, lateral view; C, habitus, ventral view; D, carapace, frontal view; E, sternum, ventral view; F, carapace, dorsal view; G, carapace, lateral view. Scale bar: A = 1 mm.

FIGURE 39. Ischnothyreus habeggeri sp. nov. Male: A, opisthosoma, dorsal view; B, opisthosoma, lateral view; C, opisthosoma, lateral view; D, leg I; E, leg II; SEM images: F, sperm pore, ventral view; G, tarsal organ of leg II; H, tarsal organ of leg III. Scale bars: F = 20 µm; G, H = 2 µm.

FIGURE 40. Ischnothyreus habeggeri sp. nov. Male: A, G, left palp, prolateral view; B, H, left palp, retrolateral view; C, E, left embolus, prolateral view; D, F, left embolus, retrolateral view. rl, retrolateral lobe; w, wrinkles. Scale bars: A, G = 0.1 mm.

FIGURE 41. Ischnothyreus habeggeri sp. nov. Male: A, chelicerae, anterior view; B, chelicerae, anterior view; C, left chelicerae, anterior view; D, left chelicerae, posterior view. p, process. Scale bars: A, B, C = 0.1 mm.

FIGURE 42. Ischnothyreus habeggeri sp. nov. Male, SEM images: A, right palp and endite, ventral view; B, left palp with gnathocoxa and endoskeletal element, lateral view; C, embolus, ventral view; D, embolus, dorsolateral view. ee, endoskeletal element; eo, embolic opening. Scale bars: A = 0.1 mm; B = 0.2 mm; C, D = 20 µm.